Question 667359

{{{U^2 - U - 12 = 0}}}....use quadratic formula

as you can see, {{{a=1}}}, {{{b=-1}}}, and {{{c=-12}}}


{{{U = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}


{{{U = (-(-1) +- sqrt((-1)^2-4*1*(-12) ))/(2*1) }}}


{{{U = (1 +- sqrt(1+48 ))/2 }}}


{{{U = (1 +- sqrt(49 ))/2 }}}


{{{U = (1 +- 7)/2 }}}


solutions:


{{{U = (1 + 7)/2 }}}


{{{U = 8/2 }}}


{{{highlight(U = 4) }}}


and


{{{U = (1 - 7)/2 }}}


{{{U = -6/2 }}}


{{{highlight(U = -3) }}}